Several things I would offer:

1) MANAGE THIS PUPPY BETTER. Put things away. Use baby gates. Keep things out of his reach. NEVER have him loose in the house when you cannot pay direct attention to him. When he is loose in your house, keep a buckle collar on him with a short cord attached that you can get hold of. ALWAYS try trading first, but if you have no time to trade, if you will take the collar or the cord and gently lift him up off his front feet, he will spit out whatever he has. The key word here is GENTLY. Lift GENTLY straight up, and he will spit out whatever he has in a couple seconds. IMMEDIATELY lower him, keeping him away from the object, and praise him, offering a treat as SOON as you can.

2) play trade A LOT. Start with 3 items. 2 low value items, such as toys he likes, and some really high value food treats cut into tiny pieces that he will gulp in a flash. Give him the toy, let him play with it a second, and then offer him a treat. As he is spitting out the toy to take the treat, say OUT. Or whatever word you choose, it can be GIVE, or MINE, or whatever you like. They KEY is for the puppy to hear this word everytime he is spitting something out. Eventually he will learn that this word means "spit that out and you will get a cookie".

3) get in training class as the others advise. You will exercise the puppy's brain along with his body and you will all benefit.

4) STOP doing what incites him to bite any of you. STOP it IMMEDIATELY, and insist your family members do the same. Make the PEOPLE take responsibility for keeping inappropriate items out of reach of the puppy.

5) Make the puppy a TOY BOX. I am will be posting another thread called "Why Your Puppy Needs a TOYBOX". I encourage you to read it and print it out so your family can read it as well.

Do an internet search on resource guarding, and another one on BITE INHIBITION, and print out the info so your family members can also understand how to address this issue with your puppy.

It is important that you pay close attention to resolving this, as it will only get worse over time if you do not.

I will post the toybox article in just a few seconds.